Harley worked with McCluggage in his year in charge of government ICT before retiring from both the government CIO role – a role that is now filled by Andy Nelson – and his role as CIO of the Department of Work and Pensions (DWP), in spring this year.

In July, McCluggage told Computing that a lack of metrics in government IT was damaging its aim for greater efficiency.

In an exclusive interview with Computing, Harley, who now works as strategic adviser at technology solutions provider Amor Group, said that there had been progress with metrics in government ICT but conceded that there was still work to be done.

"Metrics is key in all of government IT and if we can't measure it, we can't manage it. I think there has been a lot of progress in gathering of metrics but it is hard to acquire really good cross-government metrics, so that we can properly measure the progress and performance [of ICT]. There has been a lot of effort into this but there is probably a bit more to do to get the really powerful metrics which we need," he said.

McCluggage had also criticised the government's approach to cyber security, describing the pace of change as "glacial" – something that Harley strongly refuted.

"I did not see [a glacial change] in the areas that I operated in the DWP. I'm not sure about other parts of government – perhaps Bill had some visibility but I didn't see that. I thought there was a real impetus for change – it is such an important topic so I wouldn't say that there is a slow pace," he said.

Harley also defended government IT for being what McCluggage labelled "an extremely risk-averse environment".

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